Flexible stay-bolt.



W. A. KEITH.

FLEXIBLE STY BOLT.

APPL|cAT|oN,.F|Ln ocr. 28. 1914.

Patented Jn.18,1916.

F QQ@ egg@ THE coLUMBlA PLANOGLAPH 510.. wAsHlNuToN. D. c.

FLEXIBLE surnom.

specificati@ bf Letters Patent. Paten-te@ Jan, 187 1916.

Application :nea ottenerne, 1914. 'sei-iai No. 869,010.

To aZZ'fw/Lom t may concern." f

Be it known that I, `WAL'IER A. KEITH, a

citizen of the United States, residing at Los 4 Angeles, in the county of Los Angeles and 5 State of California, have invented ra new and useful ^`Flexible Stay-Bolt, of which the folL .lowing is a specification.

The primary object of this invention is to provide a novel .connecting'means between the side and crown sheets of a lire box and the wrapper sheet thereof. i

One of the most serious difliculties met with in fire box `construction yis occasioned by the great amountof expansion and con traction of the side and crown sheets, which causes the stay bolts tosnap andto become loose at their points of connection with the wrapper sheets. The plates composing the e fire box wrapper sheet vary from one and one-half times to double the thickness ofthe plates composing the crown and sidesheets, and since the plates'of the Wrapper sheet are covered with lagging and a jacket, they are protected from variation in outside temperatures. rlhe other side of the wrapper sheet plates is covered withy water and steam having an average temperature, 387.7 `degrees Fahrenheit. Hence, Athese plates have very e little expansion and contraction compara:

tively speaking. The plates composing the side and crown sheets vary in temperature from that of the atmosphere to 2800 degrees Fahrenheit, and therefore are subject 'to extreme contraction andk expansion. Rigid stay bolts 'securely yfastening the side and crown sheets to the wrapper sheet become strained and distorted because of this kbonstant expansion andcontraction of the crown and side sheet, and also enlarge theopenings 40 in the crown and side sheetsfcausing leakage.

My invention aims to provide a means which will so connect several ksheets of a boiler so as to overcome these dilhculties, said means being strong, practical and cheaper of maintenance.

With these and other objects in view, the invention consists of certain novel features of construction, combination and arrangement of parts, as will be hereinafter described, illustrated and claimed.

Referring to the drawings: Figure 1 is a rear elevation of a half of a lire box with the back plate removed. Fig. 2 is a section taken on the plane of line 2-2, of Fig. 1. Fig. 3 is a fragmentary vertical sectional view through the boiler, showing my improved connecting means. Fig. t is a Vsection taken onthe plane of line H of Fig. 1. Fig. 5 1s a fragmentary vertical sectional view showing the relative position `of the crown and side sheets ofthe fire box when expandn ed.y Fig. 6 is a detail side velevation partly in section ,of one ofthe rivets. Fig. 7 is a perspective view of a somewhat spherical nut forming a part of the flexible stay bolts.

Referring in detail to the drawings by numerals, 1 designates the fire box wrapper sheet, 2 the ylire. box side and crown sheets, 3 a Imud ring, and 4 the tube plate,all offwhich elements are of the usual construction found in a locomotive boiler.

In carrying out my invention, l provide a plurality of girders or anchoring bands 5, which are placed between the wrapper sheet and the 'fire 'box crown and side sheets and which may be of any length desiredand arranged in any manner suitable for the purpose intended. These anchor bands are preferably made concavo-convex in cross section, as best shown in Fig. 4, and are secured to the fire box crown `and side sheets 2 in spaced relation thereto by any suitable fasteners such as the rivets` 6 and 7. The rivets 6 have conical 'heads Q8, 'extend through openings in the anchor bands, and have their inner extremities 9 of a reduced diameter to form a shoulder 10 engaging the outer walls of the fire box crown and side sheets i2. The reduced portions 9 extend through the sheets of the crown and side sheets and are riveted thereto. A collar or spacing washer 11 sur rounds the shank of the rivets to maintain the anchoring bands at a iixed distance from the crown and side sheets.

The fasteners 7 are similar to vthe fasteners 6 with the exception that they have many sided heads 12 and a threaded reduced shank portion 13. Each of the fasteners 6` and 7 is providedwith a tell-tale hole 6', as shown in Fig. 6. The specific construction of these fasteners is unimportant so long as they serve to hold the bands rigidly to the crown and side sheets.

The bands are placed wherever it is desired to locate a series of stay bolts, and are formed with a plurality of rectangular slots 14 running longitudinally thereto. The stay bolts are designated as entireties by the numeral 15 and comprise T-bolts 18, sleeves 17, ball nuts 1S, and caps 19. The heads 2O of the T-bolts will pass through the slots 14 when positioned in one direction, but will transversely thereto. The other ends of the stay bolts are threaded and carry nuts 18 which are of semi-spherical. construction having faces which work within the semispherical sockets 21k of the sleeves 17. Each sleeve is externallythreaded at one end to engage a threaded opening 22-formed in the fire box wrapper sheet, and similarly threaded at its outer end to engage the interiorly threaded cap 19. Intermediate the two sets of threads a wrench flange 23 is formed.

p In assembling a fire box of this construction, the anchor bands are first secured to the fire box crown and side sheets, then the T-bolts are passed through the registering openings in the fire box wrapper sheet and Vthe anchorbands, and turned so that the heads will extend transversely of the slots 14. Next, the sleevesv23 may be Ythreaded into the openings 22 and finally the nuts 18 and caps 19 are positioned. As will be clearly apparent Vupon refcrenceto Fig. 5, my connecting means between the inner and outer sheets allows for the expansion and contraction of the sheets thereof without placing undue strain upon the stay bolts.V In this figure, the side sheet of the fire box is shown in its expanded position, at which time the openings 4: have been moved into their uppermost positions, raising the inner ends of the stay bolts slightly and causingthe ball nuts 18 to turn in the sockets 21 of the sleeve 17. The stay bolts may be easily removed by reversing the operations just described so as to permit the space between the sheets to be cleaned, and these bolts,`as wellas the anchor bands, may also be used in other fire boxes and so have a long period of usefulness. The stay bolts now commonly employed can never be used except in connection ,with the fire box to which secured, and this makes it necessary to discard the entire lire box as soon as the plates become weakened.

From the foregoingrdescription taken in connection with the accompanying drawings,

v it will be seen that I have provided a very practical fireY box construction, making use of flexible stay bolts and of' anchor plates of such design that the stay bolts and anchor plates may be used again after the original fire box has become unfit for further use.

Ido not wish to be limited to the exact construction herein shown and described, but may make such changes as will fall within the scope and spirit of the appended claims.

That I claim is:

1. The combination with a fire box comprisingv side and crownsheets and a wrapper sheet, of an anchoring band secured to the outer surface of the fire box, crown and side sheets, and stay means pivotally secured to the wrapper sheet and having a sliding connection to the anchoring band.

(2. A fire box, comprising side and crown sheets and a wrapper sheet, a band rigidly secured to the crown and side sheet between the two latter and the wrapper sheet, said band being provided with a plurality of elongated openings, and stay bolts connecting the wrapper sheet to the crown and side sheets, said stay bolts having Shanks passing through the openings in the anchor bolt, a ball-nut threaded onto one endv of said bolt, a sleeve having a socket Ato accommodate said ball nut, and a cap threaded on the outer end ofsaidsleeve. Y Y

In testimony whereof, I have hereunto set my lhand at Los Angeles, Los Angeles, this 20th day of October, 1914. 1 VALTER A. KEITH, In presence of VLORRAIN E. DURRow,

RODNEY M. SMITH.

Copies 0f this patent may be obtained for ve cents each, by addressing the Commissioner of Patents.

i Washington, D. C.

4. A stay bolt comprising a T-shaped 

